Of course, several factors make fans somewhat concerned about Bolduc's potential. First, the eye test is one thing, but he lacked scoring. For a supposed offensive defenseman who put up good numbers in the AHL, three points - and just one goal - in 17 NHL games is not a good sign.
Even if you're willing to accept that the offense will come - which it might not - the defense is even more concerning. When Bolduc was on the ice, the Islanders generated 52% of the shots on goal, which sounds good - but Bolduc started 43.6% of his shifts in the offensive zone and just 23.6% in the defensive zone. With that context, Bolduc's 52% shots-for generation looks quite bad - after all, the Islanders also had 52% of the shots when Adam Pelech was on the ice, and Pelech started only 26% of his shifts in the offensive zone.
Also, for a young player, development - playing time against good competition is essential, and I'm not sure where Bolduc will be getting development next year. He doesn't seem to have a spot in the NHL lineup, with Pelech, Ryan Pulock, Aho, Dobson, Romanov, and Scott Mayfield all returning. Perhaps he'll outcompete Aho for a spot, but that seems unlikely.
He could, of course, return to Bridgeport, where he'll certainly get playing time. But given that he's already proven he can produce at an AHL level, it's not clear whether that'd benefit him. Maybe he'll be able to work on his defense more under Kowalsky, who acknowledged that that was an area for improvement.
"I just think confidence, in [Bolduc's] ability to defend, I think there's still room to improve."- Rick Kowalsky
There's another route - what I might call the Sebastian Aho Option. In other words, sitting in the press box as the healthy scratch, taking warmups with the team but never playing unless there's an injury. It's a painful option, and I don't think it would be good for his development... but it did work for Aho.
We'll see if and how Bolduc fits into the Islanders' lineup next season. I'd be surprised if he didn't play any NHL games, but I'd also be surprised if he played more than 15 or 20 (unless there's a longterm injury). This may have to be a "wait and see" year for Bolduc.